Small vessel vasculitides

Small vessel vasculitis may be associated with immune complex disease, such as Henoch Schonlein purpura or systemic lupus erythematosus, or primary such as Wegener's granulomatosis, microscopic polyangiitis, and renal limited vasculitis. These primary conditions are associated with circulating anti-neutrophil cytoplasm antibodies and are the most common cause of rapidly progressive glomerulonephritis. This review describes recent advances in the understanding of the pathogenesis underlying these conditions and reviews common presentations. Consideration is given to recent clinical trials in the management of anti-neutrophil cytoplasm antibodies (ANCA)-associated vasculitides.